Ce compounds feature a remarkable diversity of electronic properties, which motivated extensive investigations over the last decades. Inelastic neutron scattering represents an important tool for understanding their underlying electronic structures but in certain cases a straightforward interpretation of the measured spectra is hampered by the presence of strong vibronic couplings. The latter may give rise to extra spectral features, which complicates the mapping of experimental data onto standard multiplet diagrams. To benchmark the performance of embedded-cluster quantum chemical computational schemes for the case of 4f systems, we here address the Ce 4f1 multiplet structure of NaCeO2, an antiferromagnet with D2d magnetic-site symmetry for which neutron scattering measurements indicate only weak vibronic effects. Very good agreement with the experimental results is found in the computations, which validates our computational approach and confirms NaCeO2 as a 4f magnet in the intermediate coupling regime with equally strong 4f-shell spin-orbit and crystal-field interactions.
@article{arxiv.2203.06394,
title = {Crystal-field effects competing with spin-orbit interactions in NaCeO$_2$},
author = {Pritam Bhattacharyya and Ulrich K. Rößler and Liviu Hozoi},
journal= {arXiv preprint arXiv:2203.06394},
year = {2022}
}